Incidence and influencing factors of aldosterone breakthrough during therapy with angiotensin Ⅱ receptor blockers alone,or combined with angiotensin?converting enzyme inhibitors in patients with non?diabetic nephropathy

Objective To investigate the incidence and influencing factors of aldosterone breakthrough during therapy with angiotensin II receptor blockers (ARB) alone, or combined with angiotensin?converting enzyme inhibitors（ACEI） in Chinese patients with non?diabetic nephropathy. Methods A total of 144 patients with non?diabetic nephropathy were treated with ARB or combination therapy of ACEI and ARB for a mean follow?up period of 12 months. Aldosterone breakthrough was determined according to the change of plasma aldosterone concentration before and after treatment during 6?month and 12?month ACEI/ARB treatment. Results In 6 months, aldosterone breakthrough occurred in 21 patients, corresponding to 14.58%, while in 12 months, occurred in 39 patients, corresponding to 27.08%. Although the overall urinary protein excretion (UPE) decreased after treatment in both groups (P<0.05), non?breakthrough group had a more remarkable reduction in UPE (P<0.05). Univariate Logistic regression demonstrated that risk factors of aldosterone breakthrough included pre?treatment values of UPE (OR=3.643, P=0.073) and eGFR（OR=0.980, P=0.025）. Multivariate Logistic model revealed pre?treatment values of eGFR was positively associated with aldosterone breakthrough (OR=0.980, P=0.025). Conclusions The incidence of the aldosterone breakthrough increases with duration of treatment. The patients with aldosterone breathrough have higher level of UPE, and enhanced decline in eGFR. Pre?treatment value of eGFR is independent risk factor of aldosterone breakthrough.     

Aldosterone breakthrough during therapy with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers in proteinuric patients with immunoglobulin A nephropathy

BACKGROUND: We are investigating whether aldosterone breakthrough negatively impacts on the antiproteinuric effects of angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin II receptor blockers (ARB). METHODS: We examine the role of aldosterone breakthrough in 43 normotensive, proteinuric (0.7 +/- 0.3 g/day) outpatients (aged 41.5 +/- 10.9 years) with immunoglobulin A nephropathy (IgAN) accompanied by stable renal function (creatinine clearance >50 mL/min). The patients were treated with temocapril (1 mg; n = 14), losartan (12.5 mg; n = 16), or a combination therapy (n = 13) for 12 months. We prospectively evaluated blood pressure (BP), urinary protein excretion (UPE), biochemical parameters and the renin-angiotensin-aldosterone system before and after 12 months of treatment. RESULTS: Although the overall plasma aldosterone concentrations values did not change after any of the treatments administered for 12 months, they eventually increased in 23 (temocapril, seven patients; losartan, eight patients; combination, seven patients) of the 43 patients (53.4%; aldosterone breakthrough), and fell in the remainder (46.6%). Blood pressure and renal function did not differ among the three groups at 12 months. In contrast, UPE was significantly higher in patients with, than without aldosterone breakthrough during temocapril and losartan administration. However, combination therapy induced a more remarkable reduction in UPE regardless of aldosterone breakthrough. CONCLUSIONS: A combination of ACE inhibitors and ARB in normotensive patients with IgAN produces a more profound decrease in proteinuria than either monotherapy. This additive antiproteinuric effect is not dependent on aldosterone breakthrough. Additional larger, prospective, randomized studies will be needed for general acceptance of this strategy.     

Antifibrotic Effects of Aldosterone Receptor Blocker (Spironolactone) in Patients with Chronic Kidney Disease

Aims. Proteinuria and transforming growth factor β (TGF-β) are parameters that can lead to glomerulosclerosis and tubulointerstitial fibrosis. All components of the renin-angiotensin-aldosterone system (RAAS) activate the TGF-β. Aldosterone may not be inhibited with angiotensin-converting enzyme inhibitors (ACEIs) and/or angiotensin receptor blockers (ARBs) due to aldosterone escape. We aimed to evaluate the effect of spironolactone on parameters leading to fibrosis. Methods. This prospective study included 30 non-diabetic chronic kidney disease (CKD) patients treated with ACEIs and/or ARBs. The patients were divided into two groups that are similar in terms of demographic parameters. 25 mg of spironolactone was added to group 1 (n = 15) for six months, though it was not administered to group 2 (n = 15). Creatinine (U-Cr), protein (U-Prot), and TGF-β1 (U- TGF-β1) were measured in spot urine sample in the beginning of study and six months later. Results. Twenty-four patients completed the study. There were no significant changes in mean blood pressure, glomerular filtration rate, creatinine, albumin, and plasma aldosterone concentrations during the observation period in either group. U-Prot/U-Cr (mg/mg Cr) was reduced from 2.43 ± 4.85 at baseline to 1.66 ± 3.51 at sixth month (p = 0.003) in group 1. In addition, U-TGF-β1/U-Cr (ng/mg Cr) was also reduced from 22.50 ± 6.65 at baseline to 17.78 ± 10.94 at sixth month (p = 0.041) in the same group. U-TGF-β1/U-Cr and U-Prot/U-Cr ratios after the sixth month were not found significant compared with baseline values in group 2. Conclusion. Spironolactone reduced both proteinuria and urinary TGF-β1 excretion in CKD patients. We consider that spironolactone would be beneficial to prevent progression of renal fibrosis in CKD.     

Treatment of kidney transplant recipients with ACEi/ARB and risk of respiratory tract cancer: a collaborative transplant study report

Whether treatment with angiotensin-converting enzyme inhibitors (ACEi) and/or angiotensin receptor blockers (ARB) increases the risk of cancer is controversial. Collaborative transplant study data were analyzed according to whether kidney transplant recipients were treated with ACEi/ARB at year 1. Twenty-four thousand and ninety patients were studied of whom 9079 (38%) patients received ACEi/ARB. There were 872 nonskin malignancies during years 2-8 posttransplant, including 107 respiratory/intrathoracic tumors. The standardized incidence ratio (SIR) for all nonskin malignancies was similar between the ACEi/ARB (1.91) and no ACEi/ARB (1.81) groups (p = 0.42). For respiratory/intrathoracic tumors, however, SIR was significantly higher with ACEi/ARB (1.65 vs. 1.09 for no ACEi/ARB, p = 0.033). Multivariate Cox regression analysis showed that ACEi/ARB treatment was not associated with an increased risk of respiratory/intrathoracic tumors in nonsmokers. In patients with a history of smoking, however, the risk of respiratory/intrathoracic tumors was 2.77 (95% CI 1.19-6.43, p = 0.018) in patients without ACEi/ARB treatment as compared to 7.10 (95% CI 3.27-15.4, p < 0.001) in patients treated with ACEi/ARB. Our data indicate that in kidney transplant recipients, ACEi/ARB treatment is associated with a significant increase in the rate of respiratory/intrathoracic tumors in the subpopulation of patients with a history of smoking.     

Combined converting enzyme inhibition and angiotensin receptor blockade reduce proteinuria greater than converting enzyme inhibition alone: insights into mechanism

Patients with various renal diseases receiving an angiotensin-converting enzyme inhibitor (CEI) were enrolled in a protocol to determine whether adding an angiotensin type 1 receptor blocker (ARB) reduces urinary protein excretion (UPE). All patients had significant proteinuria (range 517-8,562 mg/24 h) despite administration of CEI for at least 4 weeks. Following baseline measurements, losartan (50 mg/d) was started and testing was repeated at 1 month. Compared with CEI alone, combined CEI plus ARB reduced UPE by 45 +/- 8% (p < 0.005). Compared with CEI alone, CEI + ARB lowered UPE in each patient independent of baseline protein excretion or renal diagnosis. Reduction in proteinuria occurred independent of changes in mean arterial blood pressure (MAP), suggesting that the mechanism involved local changes in glomerular dynamics. If renal angiotensin II (ANG II) formation occurred despite CEI, the ANG II formed would suppress plasma renin activity (PRA), and adding an ARB would cause PRA to rise. In 7 of 10 subjects, addition of ARB to CEI increased PRA (p < 0.03) suggesting that intrarenal ANG II formation occurred in CEI-treated subjects. As a second marker of ANG II tissue activity, we measured the effects adding ARB on plasma aldosterone (ALDO). In 9 of 10 subjects, ALDO was acutely lowered (p < 0.009) suggesting that ANG II levels were incompletely blocked by CEI. We conclude that: combined CEI and ARB reduces UPE greater than CEI alone; reduction in proteinuria is independent of changes in MAP or renal diagnosis; and the additive effects of CEI and ARB are due at least in part to greater inhibition ofANG II action at the tissue level in the kidneys and adrenal glomerulosa.     

Effects of sulodexide in patients with type 2 diabetes and persistent albuminuria.

BACKGROUND: Urinary albumin excretion frequently persists in diabetic patients who are treated with angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB). Sulodexide, a glycosaminoglycan mixture of 80% heparan sulfate and 20% dermatan sulfate, has been hypothesized to reduce persistent albuminuria. We have conducted a multi-center randomized double-blind pilot study in order to determine the effect of 6 months' therapy with sulodexide on urinary albumin excretion and to address logistical issues for a full-scale trial. METHODS: A total of 149 patients with type 2 diabetes and an albumin:creatinine ratio (ACR) between 20 and 300 mg/g were randomized with equal allocation to either placebo, 200 mg of sulodexide or 400 mg of sulodexide. The primary endpoint was the achievement, at 6 months, of either 3(1) return to normoalbuminuria (ACR < 20 mg/g with a decrease of at least 25%) or (2) a decrease in ACR of at least 50% from the baseline value. All patients used a maximum tolerated recommended FDA approved dose of an ACEI or ARB for at least 60 days and had stable blood pressure prior to randomization. RESULTS: The primary efficacy endpoint was achieved in 25.3% of the patients in the two sulodexide groups combined versus 15.4% of the placebo-treated patients (P = 0.26). The primary endpoint was achieved in 33.3% (P = 0.075 for the comparison to placebo) in the sulodexide 200 mg group and 18.4% (P = 0.781) in the sulodexide 400 mg group. (No consistent patterns of side effects were observed. CONCLUSION: Based on the experience gained in this pilot study, one full-scale trial is currently being conducted to evaluate the effects of sulodexide on change in ACR in patients with persistent microalbuminuria, and a longer-term trial is underway to evaluate the effects of sulodexide on long-term renal disease progression in patients with overt proteinuria.     

Evaluation of Resistive Index by Color Doppler Imaging of Orbital Arteries in Type II Diabetes Mellitus Patients with Microalbuminuria

Objective: Resistive index (RI) is an indirect measurement of blood flow resistance that can be used to evaluate vascular damage in ophthalmologic diseases. The purpose of this study was to evaluate the association between RI values of orbital arteries by using the color Doppler imaging (CDI) in type II diabetes mellitus (DM) patients with microalbuminuria. Patients and methods: We evaluated 91 type II DM patients with microalbuminuria and 27 healthy subjects. The DM patients with microalbuminuria were grouped into two: group 1 consisted of patients with retinopathy (n = 51) and group 2 consisted of patients without retinopathy (n = 40). Healthy subjects constituted group 3 (n = 27). The mean RI values of ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary artery (PCA) were measured using CDI. Results: Compared to diabetic group 2, group 1 had significantly higher mean RIs of OA, CRA, PCA, and HbA1c levels (p < 0.001 for all). Besides, there were no statistical differences in mean RIs of OA, CRA, and PCA between the control group and group 2 (p = 1.0; p = 0.44; p = 0.67, respectively). Mean RIs of OA and PCA were significantly correlated with age in group 1 (r = 0.549, p < 0.001; r = 0.407, p = 0.003, respectively). Mean RI of CRA was significantly correlated with the duration of diabetes and age in group 1 (r = 0.296, p = 0.035; r = 0.486, p < 0.001, respectively). Conclusion: Our study indicates that RI might be a useful marker for early diagnosis and follow-up of diabetic retinopathy, and orbital RI assessment would be beneficial for diabetic patients with retinopathy.     

Does angiotensin blockade influence graft outcome in renal transplant recipients with IgA nephropathy?

BACKGROUND: IgA nephropathy (IgAN) is a frequent cause of end-stage renal disease (ESRD) and recurrent disease causes deterioration and graft loss in transplant recipients. No definitive management is known to reduce the risk or severity of recurrent IgAN, and the evidence to support the use of renin-angiotensin system blockade in such patients is limited. METHODS: All 1137 renal transplants performed at the Belfast City Hospital over a 27-year period were reviewed. A total of 75 patients with ESRD due to biopsy-proven IgAN were identified; 39 of them had been prescribed an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin-II type I receptor blocker (ARB). RESULTS: The two groups were well-matched in terms of demographic details, immunosuppressive regimens and duration of follow-up (median 65 months, range 18-261 months). The 5- and 10-year graft survivals were higher in those prescribed ACEi/ARB therapy compared with those who were not, although these differences did not reach statistical significance (92.9 vs 86.5%; P = 0.34 and 81.6 vs 72.7%; P = 0.32, respectively). These results were similar when censored for death with a functioning graft. In the group where an ACEi/ARB was not prescribed, all four with biopsy-proven recurrent IgAN progressed to ESRD, compared with three out of nine in the group treated with an ACEi/ARB. CONCLUSIONS: In transplant recipients with ESRD due to biopsy-proven IgAN, a trend towards improved 5-year and 10-year graft survival was seen in those prescribed ACEi/ARBs. All with recurrent IgAN in their grafts who were not treated with ACEi/ARB therapy progressed again to ESRD.     

Successful effect of triple blockade of renin–angiotensin–aldosterone system on massive proteinuria in a patient with chronic kidney disease

A patient with chronic kidney disease (CKD) due to membranous nephropathy with daily urinary protein excretion exceeding 5 g did not respond well to dual therapy with an angiotensin converting enzyme inhibitor (ACE-I) and angiotensin II receptor blocker (ARB). Addition of the mineralocorticoid receptor blocker (MRB), spironolactone, led to moderate reduction in daily urinary protein excretion. However, spironolactone had to be inevitably discontinued due to gynecomastia. Replacement of spironolactone with the selective MRB, eplerenone, added to the preceding treatment with ACE-I and ARB, resulted in remarkable reduction of daily urinary protein excretion to less than 0.2 g. This case suggests that triple blockade of renin–angiotensin–aldosterone (RAA) system with ACE-I, ARB, and MRB could be useful for CKD patients with massive proteinuria.     

Combination of Renal Biomarkers Predicts Acute Kidney Injury in Critically Ill Adults

Objective: Most studies so far have focused on the performance of individual biomarkers to detect early acute kidney injury (AKI) in the adult intensive care unit (ICU) patients; however, they have not determined the predictive ability of their combinations. The aim of this study was to compare the predictive abilities of plasma neutrophil gelatinase-associated lipocalin (pNGAL), urine neutrophil gelatinase-associated lipocalin (uNGAL), plasma cystatin C (pCysC), serum creatinine (sCr), and their combinations in detecting AKI in an adult general ICU population. Methods: A total of 100 consecutive ICU patients were included in the analysis. AKI was defined according to RIFLE criteria. Biomarker predictive abilities were evaluated by area under the curve (AUC), net reclassi?cation improvement (NRI), and integrated discrimination improvement (IDI). Results: AKI occurred in 36% of patients 7 days post-admission. All three novel biomarkers as well as sCr had moderate predictive abilities for AKI occurrence. The most efficient combinations (pNGAL + sCr and pNGAL + uNGAL + sCr) were selected to participate in the subsequent analyses. Both combinations, when added to a reference clinical model, increased its AUC significantly (0.858, p = 0.04). Their NRI (0.78, p = 0.0002) was equal to that of pNGAL, but higher than that of the other three biomarkers, whereas their IDI was higher than that of any individual biomarker (0.23, p = 0.0001). Both combinations had better specificities, positive likelihood ratios, and positive predictive values than those of any individual biomarker. Conclusion: The biomarker combinations had better predictive characteristics compared with those of each biomarker alone.     

Effect of high dose ramipril with or without indomethacin on glomerular selectivity

BACKGROUND: Despite the accumulating evidence of their efficacy, angiotensin-converting enzyme inhibitors (ACEi) still provide imperfect renoprotection. Up-titration above conventional doses and combined therapy with other antiproteinuric agents may serve to achieve renoprotection in patients at risk of rapid disease progression. METHODS: The effect of maximum tolerated ACEi doses (ramipril 15 mg/day, range 5 to 20) alone or combined with indomethacin (75 mg x 2/day) on urinary protein excretion (UPE) and glomerular barrier size-selective function was evaluated in 19 patients with chronic non-diabetic nephropathies and persistent proteinuria. RESULTS: Maximum ramipril doses decreased UPE more effectively than non-ACEi therapy. Proteinuria reduction was associated with significant reduction (>50%) of the non-selective glomerular membrane shunt, but did not correlate with concomitant changes in arterial pressure and renal hemodynamics, nor was it influenced by treatment duration. The reduction in UPE and sieving coefficient of the largest neutral dextrans exceeded by twofold the reduction achieved by conventional ACEi doses in historical controls with similar renal dysfunction and proteinuria, previously studied under identical experimental conditions. Indomethacin did not influence renal effects of maximum ramipril doses and was prematurely withdrawn in six patients because of reversible side effects. Serum potassium significantly increased only in combination with indomethacin and never required treatment withdrawal. CONCLUSIONS: Up-titration to maximally tolerated doses safely increases ACEi antiproteinuric effect and may serve to achieve maximum renoprotection in the long-term. Combination with indomethacin is poorly tolerated and ineffective. Innovative approaches are needed to use ACEi more effectively.     

The effect of weight loss after bariatric surgery on albuminuria

BACKGROUND: Bariatric surgery achieves long-term weight loss in obese adults with improvement of diabetes and hypertension. Little is known about the effect of this weight loss on renal parameters. METHODS: We performed a retrospective study of 94 obese adults who had Roux-en-Y gastric bypass surgery with a mean 12-month follow-up. Baseline (preoperative) mean age was 49 years, 76% were female, 37 had blood pressure (BP) >or= 140/90 mmHg and 32 had Type 2 diabetes. 73 patients had normoalbuminuria (urine albumin creatinine ratio (ACR) <30 mg/g) while 21 had microalbuminuria (ACR 30<300 mg/g). RESULTS: At follow-up (postoperative), we observed a decrease in mean body weight (133.6 to 97.9 kg, p<0.0001), mean hemoglobin A1c (6.3 to 5.6%, p<0.0001) and mean systolic blood pressure (132.7 to 114.0 mmHg, p<0.0001). There was a significant reduction in ACR (median with interquartile range) from 9.5 (5-28) to 5.5 (3-10) mg/g, p < 0.0001. Fewer patients had microalbuminuria (22.2 to 6.2%, p=0.004) after surgery. Subgroup analysis revealed that significant decrease in ACR was present in the 32 patients with diabetes (16.5 (5-67) to 6.0 (4-11) mg/g, p=0.001) and in the 37 patients with metabolic syndrome (8.0 (5-16) to 6.0 (3-13) mg/g, p=0.012), while 25 patients with obesity alone had a lower ACR (6.5 (4-13) to 4.5 (3-8) mg/g, p=0.270). Multiple linear regression analysis showed change in hemoglobin A1c (p=0.011) and baseline level of ACR (p<0.0001) to be significantly associated with change in ACR. CONCLUSION: We conclude that obese adults have a reduction in albuminuria after surgical weight loss, most importantly in patients with diabetes or metabolic syndrome.     

Microalbuminuria: a marker of systemic endothelial dysfunction during burn excision

INTRODUCTION: Systemic endothelial dysfunction characterises both burn injury and surgery and can be monitored by serial immunoassay of urine albumin (microalbuminuria). The aim of this study was to assess microalbuminuria before and during burn excision and identify factors that may influence it. METHODS: Serial half-hourly urine albumin/creatinine ratio (ACR, normal <2.3mg/mmol) was measured in 25 adult patients during 44 burn-excision procedures, at a median of 5 days post-injury. Median total body surface area (TBSA) excised was 12%. RESULTS: Pre-operative median ACR was normal rising to 3.25mg/mmol at 1.5h of surgery (p<0.05). Per-operative ACR at 0.5, 1, 2 and 2.5h were all associated with % TBSA burn excised (p<0.04). Median intraoperative ACR at 1h was 2.3mg/mmol for surgery within 48h post-injury, 1.6 for surgery at 2-7 days and 25.5 during excisions later than 1 month after injury (p<0.05). ACR at 1h was associated with CRP at 48h post-surgery (p=0.04). Per-operative ACR was also significantly correlated with post-operative complications. CONCLUSION: Systemic endothelial dysfunction of acute thermal injury assessed by microalbuminuria recurs with surgery, is minimal at 2-7 days post-burn and affected by % TBSA burn excised and post-operative complications.     

The benefits of renin-angiotensin blockade in renal transplant recipients with biopsy-proven allograft nephropathy.

BACKGROUND: Allograft nephropathy, regardless of aetiology, leads to progressive renal injury and eventual graft loss. In native kidney disease, treatment of hypertension, in particular with angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB), has proven beneficial in retarding renal function decline. In the present study, we reviewed the clinical course of a renal transplant recipient cohort that was prescribed either an ACEi or ARB for biopsy-proven allograft nephropathy. METHODS: Patients were followed from the time of post-biopsy initiation of ACEi/ARB and were stratified based on biopsy findings. Outcomes of interest included safety, allograft survival, renal function and change in slope of renal function pre- and post-ACEi/ARB. RESULTS: The 5 year allograft survival after biopsy diagnosis of allograft nephropathy was 83%. Serum creatinine was 191+/-97 (86-377) micromol/l at the time of biopsy and 228+/-102 (102-575) micromol/l at last follow-up. The slopes of reciprocal creatinine vs time were used to calculate the decline in renal function and were compared pre- and post-ACEi/ARB. The mean slope+/-SD was -0.06+/-0.21 l/micromol x 10(-3) per month in the 12 months prior to therapy and -0.03+/-0.09 l/micromol x 10(-3) per month following therapy. The absolute difference in slopes was 0.03 (P =<0.0001). CONCLUSIONS: Treatment with ACEi/ARB may be beneficial in the management of allograft nephropathy.     

Impact of blood pressure control and angiotensin-converting enzyme inhibitor therapy on new-onset microalbuminuria in type 2 diabetes: a post hoc analysis of the BENEDICT trial

For assessment of the independent renoprotective effect of BP control and angiotensin-converting enzyme inhibitor (ACEi) therapy, the relationships of baseline BP, BP reduction, and follow-up BP with the incidence of persistent microalbuminuria were evaluated in 1204 hypertensive patients who had type 2 diabetes and normoalbuminuria and were included in the BErgamo Nephrologic Diabetic Complications Trial (BENEDICT) study and were randomly assigned to 3.6 yr of treatment with the ACEi trandolapril (2 mg/d), the nondihydropyridine calcium channel blocker (ndCCB) verapamil SR (240 mg/d), their fixed combination Veratran (trandolapril 2 mg/d plus verapamil SR 180 mg/d), or placebo, plus other antihypertensive medications targeted at systolic/diastolic BP <130/80 mmHg. Follow-up (from month 3 to study end) systolic, diastolic, mean, and pulse BP and their reductions versus baseline--but not baseline BP--independently predicted (P < 0.001) the risk for microalbuminuria. In patients with follow-up BP above medians, ACEi significantly reduced the risk for microalbuminuria to levels that were observed among patients with BP below medians, regardless of ACEi treatment. The same trend was observed among patients with BP reductions below medians. ndCCB therapy did not independently affect microalbuminuria. Patients who were on Veratran had lower BP and less frequently received diuretics, beta blockers, or dihydropyridine dCCB. In hypertensive, normoalbuminuric patients with type 2 diabetes, BP reduction and ACEi therapy both independently may prevent microalbuminuria. ACEi therapy is particularly effective when BP is poorly controlled, whereas ndCCB therapy is ineffective at any level of achieved BP. As compared with trandolapril, Veratran may help with achievement of target BP with less need for concomitant antihypertensive medications.     

Gastric Yield Pressure and Gastric Yield Volume to Assess Anti-Reflux Barrier in a Porcine Model

ABSTRACT

Anti-reflux barrier (ARB) resistance may be useful to test new treatments for gastroesophageal reflux (GER). The ARB has been estimated by increasing gastric yield pressure (GYP) and gastric yield volume (GYV) in animal models but has not been validated. This study aimed to develop an experimental model suitable for assessing the ARB resistance to increasing intragastric pressure and volume and its reproducibility in a seven-day interval. Ten two-month-old female Large-White swine were studied. Intragastric pressure and volume were recorded using a digital system connected to a Foley catheter inserted through gastrostomy into the stomach. GYP and GYV were defined as the gastric pressure and volume able to yield gastric contents into the esophagus detected by esophageal pH. A sudden pH drop below 3 sustained during 5 min was considered diagnostic for gastric yield. Animals were studied again after seven days. On days 0 and 7, there were no significant differences for GYP (mean ± SD = 7.66 ± 3.02 mmHg vs. 7.07 ± 3.54 mmHg, p = .686) and GYV (636.70 ± 216.74 ml vs. 608.30 ± 276.66 ml; p = .299), respectively. Concordance correlation coefficient (ρ_c) was significant for GYP (ρ_c = 0.634, 95% CI = 0.141–0.829, p = .006), but not for GYV (ρ_c = 0.291, 95% CI = ?0.118 to 0.774, p = .196). This study demonstrated an experimental model, assessing the ARB resistance. GYP seems to be a more reliable parameter than GYV for assessment of ARB resistance.     

C4d as a significant predictor for humoral rejection in renal allografts

OBJECTIVE: To determine the diagnostic and clinical significance of C4d accumulation in renal allografts followed by acute rejection. METHODS: A total of 158 graft biopsies performed from December 1997 to December 2002 were classified, according to the Banff-97 criteria, into hyperacute rejection (HAR, three cases), acute vascular rejection (AVR, 27), acute cellular rejection (ACR, 24), borderline rejection (BR, 38), acute tubular necrosis (ATN, five), stable graft function (SGF, 30) and baseline kidney (31). Immunohistochemical technique was used to determine the C4d deposition level. RESULTS: The percentages of C4d positive in HAR, AVR, ACR, BR, ATN, SGF and baseline kidney groups were 100% (3/3), 77.8% (21/27), 37.5% (9/24), 23.7% (9/38), 0% (0/5), 3.3% (1/30), 0% (0/31), respectively. In acute rejection patients, the peak serum creatinine (sCr) level in C4d(ptc)-positive group (41 cases) was 334.82 +/- 238.37 micromol/L, with that of C4d(ptc)-negative group (47 cases) being 220.20 +/- 176.94 micromol/L (p < 0.01). After treatment, the trough sCr level in C4d(ptc)-positive group and C4d(ptc)-negative group were 176.87 +/- 111.80 and 121.75 +/- 34.59 micromol/L (p < 0.01), respectively. In each AVR, ACR and BR subgroups, the peak sCr level, the trough sCr level, after 3 or 6 months of AR, the sCr level in C4d(ptc)-positive subgroup was higher than that of C4d(ptc)-negative subgroup. There were more resistance against steroid therapy [65.9% (27/41) vs. 36.2% (17/47), p = 0.005] and a higher rate of graft loss [29.3% (12/41) vs. 6.4% (3/47), p = 0.001] in C4d(ptc)-positive group than those of C4d(ptc)-negative group. In each C4d(ptc)-positive subgroup of AVR, ACR and BR the complete reversion was 57.1, 56 and 66.7%, respectively, it is almost same. CONCLUSION: The C4d deposition level is of great value in diagnosis of acute rejection caused by humoral immune components. It is a significant predictor of graft survival and will be of great help when treating acute rejection.     

Community-acquired hyperkalemia in elderly patients: risk factors and clinical outcomes

Background: Although the risk and related factors of hyperkalemia developed in the hospital are known in elderly, risk and related factors of community-acquired hyperkalemia (CAH) in this population are not well known. This study was performed to investigate the risk of CAH in elderly and evaluate the related factors and clinical outcomes.

Study design, setting and participants, intervention: Patients (aged ≥65 years) with hyperkalemia were screened. Group 1 (young-old); 65–74 years/old, Group 2 (middle-old); 75–84 years/old, Group 3 (oldest-old); ≥85 years/old, and Group 4 (control group); ≥65 years/old (normal serum potassium levels). The relation between CAH and hospital expenses (HE), the number of comorbid diseases (NCD), and all-cause of mortality rates (MR) were evaluated. We also investigated whether drugs, sex, and NCD are risk factors for the development of CAH.

Results: There was a positive correlation between serum potassium levels and length of hospital stay, MR, HE, and NCD (p?<?0.001). Risk factors for CAH were the use of non-steroidal-anti inflammatory drugs (NSAIDs) (Odds Ratio [OR]: 2.679), spironolactone (OR: 2.530), and angiotensin converting enzyme inhibitors (ACEI) (OR: 2.242), angiotensin receptor blockers (ARB) (OR: 2.679), ≥2 comorbid diseases (OR: 2.221), female gender (OR: 2.112), and renal injury (OR: 5.55). CAH risk was found to be increased 30.03 times when any of ACEI, ARB, NSAIDs, or spironolactone is given to a patient with a renal injury.

Conclusion: Use of NSAIDs, ACEI, ARB, spironolactone and increased NCD are all independent risk factors for CAH in the elderly, especially in patients with kidney diseases.     

Effect of Spironolactone on Urinary Protein Excretion in Patients with Chronic Kidney Disease

Aim.?To investigate antiproteinuric effect of spironolactone in patients with chronic kidney disease (CKD) treated with angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin II type 1 receptor blockers (ARBs).?Methods.?This study was performed in 33 CKD patients with proteinuria. 24 h urinary protein excretion and biochemical parameters were obtained before the therapy. Then, spironolactone (25 mg/d) was added to the therapy. The antiproteinuric effect of spironolactone was examined for eight weeks.?Results.?At eight weeks, there was a significant decrease in proteinuria (p < 0.001, 47.9% decrease). Systolic and diastolic blood pressures were significantly decreased (p < 0.004, p < 0.001, respectively). However, no correlation was detected between the reductions in systolic and diastolic BP and the reduction in proteinuria (p = 0.464, p = 0.239, respectively). Serum potassium level increased significantly (p < 0.001).?Conclusions.?Our study suggests that spironolactone significantly reduces urinary protein excretion. This strategy may be useful to slow the progression of CKD. However, hyperkalemia is the most important side effect of treatment, and it is necessary to monitor potassium level. Further studies are needed to determine the efficacy of spironolactone on proteinuria.